20.3. Telephone Line Interface
<Function>
- Bell signal detection
- Clip signal detection
- ON/OFF hook circuit
- Audio circuits
Bell & Clip (: Calling Line Identification Presentation: Caller ID) signal detection:
In the standby mode, Q2 is open to cut the DC loop current and decrease the ring load.
When ring voltage appears at the TP3 (A) and TP40 (B) leads (when the telephone rings), the
signal is transferred as follows;
- A C4 R2 R29 IC2 (DLP) [BELL & CLIP]
- B C3 R1 R30 IC2 (DLP) [BELL & CLIP]
ON/OFF hook circuit:
In the standby mode, Q2 is open, and connected as to cut the DC loop current and to cut the
voice signal. The unit is consequently in an off-hook condition.
When IC2 detects a ring signal or press the TALK Key onto the handset, Q3 turns on and then Q2
turns on, thus providing an off-hook condition (active DC current flow through the circuit) and
the following signal flow is for the loop current.
- A R77 D2 Q2 R8 Q3 D2 B [OFF HOOK]
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Содержание KX-TCD412NZM
Страница 22: ... To exit the operation press any time 22 ...
Страница 51: ...18 FREQUENCY TABLE MHz 51 ...
Страница 58: ...25 CPU DATA BASE UNIT 25 1 IC2 BBIC 58 ...
Страница 73: ...30 CABINET AND ELECTRICAL PARTS LOCATION BASE UNIT 73 ...
Страница 74: ...74 ...
Страница 75: ...31 CABINET AND ELECTRICAL PARTS LOCATION HANDSET 32 CABINET AND ELECTRICAL PARTS LOCATION CHARGER UNIT 75 ...
Страница 76: ...33 ACCESSORIES AND PACKING MATERIALS 76 ...
Страница 77: ...33 1 KX TCD412NZM 33 2 KX A142NZM 77 ...
Страница 78: ...34 TERMINAL GUIDE OF THE ICs TRANSISTORS AND DIODES 34 1 Base Unit 78 ...
Страница 92: ...PbF D1 J1 CIRCUIT BOARD CHARGER UNIT Component View ...
Страница 93: ...PbF R1 R2 TP4 TP1 TP2 TP3 CIRCUIT BOARD CHARGER UNIT Flow Solder Side View ...
Страница 94: ...4 1 5 8 PbF 1 28 18 IC3 IC2 IC1 11 64 1 16 17 32 49 48 33 Marked ...
Страница 96: ...Marked PbF IC1 IC2 100 80 5 8 4 1 50 51 30 31 1 11 18 1 28 IC3 ...
Страница 97: ...Marked 1 PROG PbF BOOK UP POWER CAN DOWN RIGHT REDIAL LEFT 1 2 3 6 5 7 0 R 4 9 8 INT MIC TALK 36 CN2 ...
Страница 98: ...PbF D1 J1 Marked PbF R1 R2 TP4 TP1 TP2 TP3 Marked Component View Flow Solder Side View ...
Страница 99: ...Clip Base PCB G N D S D A S C L 2 7V MODE SDA SCLK GND J104 J103 J102 J101 J100 ...
Страница 104: ...PbF R1 R2 TP4 TP1 TP2 TP3 Digital Volt Meter 12Ω 2W A ...
Страница 114: ...TP3 R2 27 TP4 D1 2 1 J1 pinL DC_PLUG 22 Charge_minus TP1 TP2 R1 Charge_plus SCHEMATIC DIAGRAM CHARGER UNIT ...